JP6794900B2 - Manufacturing method of fluid passage device and fluid passage device - Google Patents

Description

The present invention relates to a fluid passage device having a passage through which a fluid flows, and a method for manufacturing the same.

Examples of the fluid passage device including the main passage through which the fluid flows and the body in which the branch passage branching from the main passage is formed inside the metal member include a common rail used for an internal combustion engine, a fuel pump, and a fuel injection valve. In this type of fluid passage device, stress concentration occurs at the corners where the main passage and the branch passage intersect due to the high pressure applied to the passage wall surface. Therefore, there is a concern that the intersection may be damaged, such as a chipped corner. In response to this concern, in Patent Document 1, after drilling a main passage and a branch passage, shot peening is performed in which a shot material collides with the intersection to remove tensile stress and apply residual compressive stress to the intersection. I'm letting you.

Specifically, after the through hole serving as the main passage is drilled, the injection nozzle is inserted from one opening of the through hole, and the reflective material is inserted from the other opening of the through hole. The injection nozzle injects the shot material in the through hole direction, and a reflective surface is formed at the tip of the reflective material to bounce the shot material injected from the injection nozzle in the perpendicular direction. Then, by positioning the reflective material so that the reflective surface faces the intersecting portion, the shot material collides with the intersecting portion and a residual compressive stress is applied.

Even if the main passage required for the fluid passage device has a shape in which the tip is closed, first, a through hole is drilled so that a reflective material can be inserted, and shot peening is performed. It is common to later close the other opening of the through hole with a lid.

Japanese Unexamined Patent Publication No. 2001-200773

However, in the above-mentioned conventional manufacturing method, the reflective surface is worn immediately, so that the reflective material needs to be replaced frequently. In particular, in the case of mass production of fluid passage devices, the frequency of replacement of the reflective material becomes extremely high, resulting in poor productivity.

The present inventor has also studied a manufacturing method that eliminates the need for a reflective material by using an injection nozzle capable of injecting in a direction perpendicular to the through hole direction. However, this type of injection nozzle has a structure having a reflecting surface that reflects the shot material injected in the through hole direction to change the direction of injection. Therefore, although a reflective material is not required according to this structure, wear of the reflective surface of the injection nozzle cannot be avoided in the end, and the injection nozzle needs to be replaced as the wear progresses, which is not a countermeasure for deterioration of productivity.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a fluid passage device capable of suppressing frequent replacement of worn parts and a method for manufacturing the same.

The invention disclosed herein employs the following technical means in order to achieve the above object. The scope of claims and the reference numerals in parentheses described in this section indicate the correspondence with the specific means described in the embodiments described later, and do not limit the technical scope of the invention. ..

One of the disclosed inventions is in a fluid passage device having a passage for circulating fluid.
A metal body (10, 10A) in which a closed passage (21a) having a shape extending linearly in a predetermined direction and having a closed tip and a branch passage (31a, 32a) branching from the closed passage are formed inside. With 10B)
Of the wall surfaces forming the tip of the closed passage on the closed side, the surface perpendicular to the predetermined direction is referred to as the ceiling wall surface (22), the surface parallel to the predetermined direction is referred to as the passage wall surface (21), and the ceiling wall surface and the passage wall surface. and a surface connecting the connecting wall (23), connecting walls, Ri shape der curved on the side to expand the closed channel,
Let D be the diameter of the branch passage
Let the diameter of the closed passage be Da
Let R be the radius of curvature of the connecting wall surface
Let H be the length from the ceiling wall surface to the branch passage in the predetermined direction.
Let f1 (D, Da, R) be a function that specifies the lower limit of H with D, Da, and R as parameters.
Let f2 (D, Da, R) be a function that specifies the upper limit of H with D, Da, and R as parameters.
The following Equation 1, a fluid passage apparatus that have conditions of Equation 2 and Equation 3 is satisfied.
[Formula 1]
f1 (D, Da, R) = (0.019 x Da-0.0050 x D + 0.077) x R + (0.16 x Da-0.68 x D + 0.70)
[Formula 2]
f2 (D, Da, R) = (-0.018 x Da + 0.011 x D + 0.35) x R + (0.16 x Da-0.49 x D + 1.6)
[Formula 3]
f1 (D, Da, R) ≦ H ≦ f2 (D, Da, R)

According to the above invention, among the tip wall surfaces forming the tip end portion on the closed side of the closed passage, the connecting wall surface connecting the ceiling wall surface and the passage wall surface has a shape curved to the side where the closed passage is expanded. Therefore, the shot material collides with the intersection (corner) where the wall surface of the closed passage and the wall surface of the branch passage intersect, that is, the intersection (corner) between the closed passage and the branch passage where damage due to stress concentration is feared, and the residual compressive stress is applied. Can be realized as follows. That is, if the injection nozzle is inserted through the opening of the closed passage and the shot material is injected from the injection nozzle in a predetermined direction, the injected shot material is reflected by the ceiling wall surface and collides with the intersecting portion, and in addition, the connecting wall surface is connected. It will be reflected by and will collide with the intersection. Therefore, since the body is provided with the function of reflection by the conventional reflective material, the conventional reflective material can be eliminated and frequent replacement of worn parts can be suppressed.

In one of the disclosed inventions, a closed passage (21a) having a shape extending linearly in a predetermined direction and having a closed tip and a branch passage (31a, 32a) branching from the closed passage are formed inside. In a method for manufacturing a fluid passage device having a metal body (10, 10A, 10B) and allowing fluid to flow through a closed passage and a branch passage.
A drilling step (S10) of forming a closed passage by drilling a portion of the body corresponding to the closed passage without penetrating it.
After the drilling step, the shot preparation step (S31) of inserting the injection nozzle (60) having the injection port (62) for injecting the shot material (90) into the closed passage, and the shot preparation step (S31).
After the shot preparation step, the shot step (S32) of injecting the shot material from the injection port in the insertion direction is included.
In the shot preparation step, the injection port is positioned on the front side in the insertion direction from the branch passage, and in the shot step, the shot material injected from the injection port is used as the tip wall surface (20a) forming the tip portion on the closing side of the closing passage. It is a method of manufacturing a fluid passage device which is reflected by the above and collides with an intersecting portion (11) where the wall surface of the closed passage and the wall surface of the branch passage intersect.

According to the above invention, when the shot material is made to collide with the intersection where the wall surface of the closed passage and the wall surface of the branch passage intersect, that is, the corner portion where damage due to stress concentration is feared, the shot material is applied to the tip wall surface of the body. Reflect and collide. Therefore, since the body is provided with the function of reflection by the conventional reflective material, the conventional reflective material can be eliminated and frequent replacement of worn parts can be suppressed.

Sectional drawing of the fluid passage device which concerns on 1st Embodiment of this invention. FIG. 2 is a cross-sectional view taken along the line II-II of FIG. The flowchart which shows the procedure of the manufacturing method of the fluid passage device which concerns on 1st Embodiment. The figure which shows the drill used for drilling in 1st Embodiment. FIG. 5 is a cross-sectional view showing a state in which a shot material is injected in the first embodiment. The schematic diagram which shows the reflection path of a shot material in 1st Embodiment. FIG. 5 is a cross-sectional view showing a range in which shot peening is required in the first embodiment. The figure which shows the result of simulating the relationship between the probability that a shot material collides with an intersection part and each parameter in 1st Embodiment. Sectional drawing of the fluid passage device which concerns on 2nd Embodiment of this invention. Sectional drawing of the fluid passage device which concerns on 3rd Embodiment of this invention.

Hereinafter, a plurality of modes for carrying out the invention will be described with reference to the drawings. In each form, the same reference numerals may be given to the parts corresponding to the matters described in the preceding forms, and duplicate description may be omitted. When only a part of the configuration is described in each form, the other parts of the configuration can be applied with reference to the other forms described above.

(First Embodiment)
The fluid passage device according to the present embodiment is applied to a high-pressure fuel pump mounted on a vehicle. The high-pressure fuel pump pressurizes fuel to a high pressure equal to or higher than a predetermined pressure, and supplies the high-pressure fuel (fluid) to the common rail. The common rail accumulates high-pressure fuel supplied from the high-pressure fuel pump and distributes it to a plurality of fuel injection valves. The fuel injection valve injects the distributed high-pressure fuel into the combustion chamber of the internal combustion engine. The high-pressure fuel pump includes a bag hole cylinder 10 (see FIG. 1) and a piston (not shown), and the low pressure fuel flowing into the bag hole cylinder 10 is compressed by the piston and pumped to the common rail.

As shown in FIG. 1, the bag hole cylinder 10 is a metal part having a cylinder portion 20 and a discharge portion 30. The cylinder portion 20 and the discharge portion 30 are integrally formed by cutting a metal base material, and the bag hole cylinder 10 is made of metal in which a closing passage 21a and a branch passage, which will be described in detail later, are formed therein. Corresponds to "body". Fuel is compressed by a piston (not shown) in the cylinder portion 20, and the high-pressure fuel compressed by the cylinder portion 20 is discharged from the discharge portion 30 to the common rail.

Inside the cylinder portion 20, a closed passage 21a having a shape extending linearly in a predetermined direction (vertical direction in FIG. 1) and having a closed tip is formed. The closed passage 21a has a circular cross section, and the direction in which the center line C1 of the closed passage 21a extends corresponds to the predetermined direction. The opening 21b of the closed passage 21a located on the end surface of the cylinder portion 20 is circular when viewed from the center line C1 direction, and the portion of the cylinder portion 20 forming the opening 21b has a cylindrical shape extending in the center line C1 direction. .. The center line of the cylinder portion 20 and the center line C1 of the closed passage 21a coincide with each other.

As shown in FIGS. 1 and 2, among the wall surfaces forming the tip portion of the closed passage 21a on the closed side, the surface perpendicular to the center line C1 direction (predetermined direction) of the closed passage 21a is called the ceiling wall surface 22. The surface parallel to the center line C1 direction is called the passage wall surface 21. The passage wall surface 21, the ceiling wall surface 22, and the connecting wall surface 23 are integrally formed of metal by cutting. The surface connecting the ceiling wall surface 22 and the passage wall surface 21 is referred to as a connecting wall surface 23. Reference numeral A1 in FIG. 2 indicates a region of the passage wall surface 21, reference numeral A2 indicates a region of the ceiling wall surface 22, and reference numeral A3 indicates a region of the connecting wall surface 23.

The passage wall surface 21 is an annular peripheral surface centered on the center line C1 and has an annular shape when viewed from the center line C1 direction. The ceiling wall surface 22 is a flat surface extending perpendicularly to the center line C1 and has a disk shape when viewed from the center line C1 direction. The connecting wall surface 23 has a shape extending in an annular shape about the center line C1 and curved toward the side where the closed passage 21a is expanded. In other words, it is an arc shape curved outward in the radial direction in a cross-sectional view including the center line C1.

In the present embodiment, the wall surface forming the tip portion of the closed passage 21a on the closed side may be referred to as the tip wall surface 20a, and the tip wall surface 20a includes at least the ceiling wall surface 22 and the connecting wall surface 23. The passage diameter of the closed passage 21a is uniform in the region of the passage wall surface 21 indicated by reference numeral A1, and gradually decreases in the region of the connecting wall surface 23 indicated by reference numeral A3.

Branch passages 31a and 32a branching from the closed passage 21a are formed inside the discharge portion 30. The direction in which the center line C2 of the branch passages 31a and 32a extends is orthogonal to the direction (predetermined direction) of the center line C1. The branch passages 31a and 32a have a circular cross section. The opening 31b of the branch passage 31a located on the end surface of the discharge portion 30 is circular when viewed from the center line C2 direction, and the portion of the discharge portion 30 forming the opening 31b has a cylindrical shape extending in the center line C2 direction. .. Further, due to the fact that the center line C2 of the branch passages 31a and 32a is orthogonal to the center line C1 of the block passage 21a, the communication port 32b communicating with the block passage 21a among the branch passages 31a and 32a is in the direction of the center line C2. It is circular in sight.

The communication port 32b has a smaller diameter than the opening 31b formed on the end face of the discharge portion 30. That is, of the branch passages 31a and 32a, the portion including the communication port 32b is called the small diameter branch passage 32a, the portion including the opening 31b is called the large diameter branch passage 31a, and the passage diameter of the small diameter branch passage 32a is the large diameter branch passage 31a. It is set smaller than the passage diameter of. The wall surface forming the large-diameter branch passage 31a is referred to as a large-diameter wall surface 31, and the wall surface forming the small-diameter branch passage 32a is referred to as a small-diameter wall surface 32. The communication port 32b is formed on the passage wall surface 21. Specifically, the entire communication port 32b is located on the passage wall surface 21. In other words, the entire connecting wall surface 23 is located on the side of the ceiling wall surface 22 with respect to the communication port 32b.

Of the bag hole cylinder 10 (body), the portion where the passage wall surface 21 of the closed passage 21a and the small diameter wall surface 32 of the branch passage intersect is referred to as an intersection portion 11. The intersection portion 11 is a portion around the communication port 32b, and the portion (corner portion) of the intersection portion 11 adjacent to the communication port 32b has a right-angled shape in the cross-sectional view of FIG. Shot peening, which will be described later, is applied to the intersecting portion 11, whereby tensile stress is removed and residual compressive stress is applied.

Next, the manufacturing procedure of the bag hole cylinder 10 included in the high-pressure fuel pump (fluid passage device) will be described with reference to FIG.

First, the outer surface of the metal base material is cut to prepare a metal processed product in a state in which the closed passage 21a and the branch passages 31a and 32a are not formed. Next, in step S10 (drilling step) of FIG. 3, a drilling process is performed to drill a hole in the metal processed product to form a closed passage 21a.

In the drilling according to the step S10, first, in the step S11, a pilot hole 210a is formed in the portion of the body corresponding to the closed passage 21a without being penetrated by the pilot hole drill 51 shown in FIG. In the subsequent step S12, the pilot hole 210a is cut to a desired diameter with the rough finishing drill 52. In the subsequent step S13, the connecting wall surface 23 is cut to a desired radius of curvature with the tip R processing drill 53.

After the closed passage 21a is drilled in the step S10, in the subsequent step S20, the metal processed product in which the closed passage 21a is formed is drilled to form the branch passages 31a and 32a. To be described in detail, first, a pilot hole is formed in a portion of the body corresponding to the branch passages 31a and 32a with a pilot hole drill. Next, the small-diameter branch passage 32a is formed by the small-diameter drill, and then the large-diameter branch passage 31a is formed by the large-diameter drill.

After drilling the branch passages 31a and 32a in step S20, in the subsequent step S30, shot peening is applied to the intersecting portion 11 of the body, that is, the portion to which the residual compressive stress is to be applied. Specifically, first, in step S31 (shot preparation step), the injection nozzle 60 shown in FIG. 5 is inserted into the closed passage 21a through the opening 21b. The injection nozzle 60 is a pipe that injects a shot material 90 such as glass beads. A shot passage 61 for circulating the shot material 90 is formed inside the injection nozzle 60, and the shot material 90 is injected from the injection port 62 which is the opening of the shot passage 61.

The injection nozzle 60 is positioned so that the center line C3 of the injection nozzle 60 coincides with the center line C1 of the closed passage 21a. Further, the injection nozzle 60 is positioned so that the injection port 62 is located on the front side (opening 21b side) of the communication port 32b and the injection port 62 faces the ceiling wall surface 22. After positioning the injection nozzle 60 in this way, in the subsequent step S32 (shot step), the shot material 90 is injected from the injection port 62.

As shown in FIG. 6, the shot material 90 injected from the injection port 62 is reflected by the ceiling wall surface 22 and the connecting wall surface 23 (tip wall surface 20a), and then the portion of the body intersecting portion 11 that forms the passage wall surface 21. It collides with the modified surface 11a. The portion with halftone dots in FIG. 7 corresponds to the modified surface 11a, which is the portion to which the shot material 90 is to collide.

The path Y1 shown by the solid line in FIG. 6 indicates a path in which the shot material 90 injected from the injection port 62 collides with the ceiling wall surface 22 and then collides with the modified surface 11a. The path Y2 shown by the dotted line in FIG. 6 indicates a path in which the shot material 90 injected from the injection port 62 collides with the connecting wall surface 23, then collides with the ceiling wall surface 22, and then collides with the modified surface 11a. The path Y3 shown by the alternate long and short dash line in FIG. 6 indicates a path in which the shot material 90 injected from the injection port 62 collides with the connecting wall surface 23 and then collides with the modified surface 11a. Paths Y1 and Y3 are examples of reflecting once on the tip wall surface 20a and then colliding with the modified surface 11a, and paths Y2 are examples of reflecting twice on the tip wall surface 20a and then colliding with the modified surface 11a. is there.

Of the shot materials 90 injected from the injection port 62, it is desirable to reduce the shot materials 90 that do not collide with the modified surface 11a. Further, even when it collides with the modified surface 11a, it is desirable that the number of reflections on the tip wall surface 20a is 2 times or less. That is, it is desirable that as many shot materials 90 as possible collide with the modified surface 11a with a number of reflections of 2 times or less, and various dimensions described below are set so as to achieve such a desirable collision mode.

As shown in FIGS. 6 and 7, the diameter of the closed passage 21a is Da, the diameter of the small diameter branch passage 32a (branch passage) is D, and the radius of curvature of the connecting wall surface 23 is R. Further, let H be the length in a predetermined direction from the small diameter branch passage 32a to the ceiling wall surface 22. Specifically, let H be the length in a predetermined direction (center line C1 direction) from the end of the communication port 32b on the ceiling wall surface 22 side to the ceiling wall surface 22. Further, the length from the branch passage to the injection nozzle 60 in a predetermined direction is defined as Ha. Specifically, the length of the communication port 32b from the end on the injection nozzle 60 side to the injection port 62 in a predetermined direction (center line C1 direction) is defined as Ha.

The present inventor describes how the probability of collision with the modified surface 11a changes with the number of reflections of 2 or less when the above-mentioned five parameters of Da, D, R, H, and Ha are changed. I simulated it. FIG. 8 is a diagram showing the simulation results, and shows the relationship between the probability that the shot material 90 collides with the modified surface 11a with reflection within two times and each parameter.

In this simulation, the combination of each parameter is No. 1-No. Set about 23 ways up to 23, and No. 1-No. The above probabilities under each of the 23 conditions are calculated. The values of each of these 23 parameters are created based on the Design of experiments (DOE).

For example, No. in FIG. The combination of parameters shown in 8 is R = 0.5 mm, H = 3.2 mm, Da = 6.42 mm, D = 1 mm, Ha = 3 mm. Under this condition, out of 100 shots ejected at equal angular intervals, the number of shot materials 90 that collide with the modified surface 11a without being reflected on the wall surface is two, and the shot material 90 is reflected once on the tip wall surface 20a and modified. The number of shot materials 90 that collide with the surface 11a is 6, and the number of shot materials 90 that collide with the modified surface 11a after being reflected twice by the tip wall surface 20a is 11. Therefore, the number of shot materials 90 that collide with the modified surface 11a with the number of reflections of 2 or less is 19 out of 100. Therefore, the probability of colliding with the modified surface 11a with the number of reflections of 2 or less is 19%. In this way, the probabilities calculated for the 23 conditions are shown in the rightmost column of FIG.

Next, the relationship between the five parameters and the above probabilities is calculated from the simulation results shown in FIG. For example, a response surface methodology (RSM) is used to search for a combination of parameter values having a maximum probability (maximum probability). Next, the range of the parameter including the value of the parameter having the maximum probability and having the probability of 95% or more with respect to the maximum probability is calculated. According to the calculation result, the following can be derived. That is, if the four parameters Da, D, R, and H are set so that the conditions of the following formulas 1, 2, and 3 are satisfied, a high probability (collision) such that the above-mentioned maximum probability × 95% or more is obtained. Probability) can be obtained. However, it is premised that Ha is set in the range of 0 mm to 3 mm.
[Formula 1]
f1 (D, Da, R) = (0.019 x Da-0.0050 x D + 0.077) x R + (0.16 x Da-0.68 x D + 0.70)
[Formula 2]
f2 (D, Da, R) = (-0.018 x Da + 0.011 x D + 0.35) x R + (0.16 x Da-0.49 x D + 1.6)
[Formula 3]
f1 (D, Da, R) ≦ H ≦ f2 (D, Da, R)

In short, f1 (D, Da, R) described in Equation 1 is a function that specifies the lower limit of H with D, Da, and R as parameters. F2 (D, Da, R) described in Equation 2 is a function that specifies the upper limit value of H with D, Da, and R as parameters. Further, the present inventor has confirmed that the above formulas 1 to 3 are valid for the three patterns of Ha = 0, Ha = 1.5, and Ha = 3.

The diffusion angle θ (see FIG. 5) of the shot material 90 injected from the injection port 62 is likely to actually be in the range of 90 ° to 120 °, and in the above simulation, the diffusion angle θ is 120 °. Is a condition. However, the present inventor has confirmed that the above equations 1 to 3 are valid as long as the diffusion angle θ is in the range of 90 ° to 120 ° even if the diffusion angle θ is other than 120 °.

In view of this point, in the present embodiment, the injection nozzle 60 is positioned so that Ha is in the range of 0 mm to 3 mm in step S31, and the shot is shot so that the diffusion angle θ is in the range of 90 ° to 120 ° in step S32. The material 90 is injected. Therefore, the shot material 90 injected from the injection port 62 should collide with the modified surface 11a with a collision probability of maximum probability × 95% or more.

In the above simulation, in determining whether or not the shot material 90 collided with the modified surface 11a, it was determined that the shot material 90 collided with the modified surface 11a when it collided with a region in which the communication port 32b was expanded by 1 mm in the radial direction. It is a condition to do. Since the collision probability becomes even higher when the enlarged area is set to be larger than 1 mm, it can be said that the above simulation is conditional on setting the enlarged area to 1 mm or more.

Contrary to this embodiment, when H is made smaller than the lower limit value f1 (D, Da, R), the number of shot materials 90 colliding with the modified surface 11a is reduced by the path Y2 shown in FIG. 6, and the modified surface 11a The probability of collision with is low. Contrary to this embodiment, when H is made larger than the upper limit value f2 (D, Da, R), the number of shot materials 90 colliding with the modified surface 11a is reduced by the path Y3 shown in FIG. 6, and the modified surface 11a The probability of collision with is low.

Further, in step S10, the closed passage 21a is formed so that the values of Da, D, R, and H satisfy all the conditions of Formula 1, Formula 2, and Formula 3. For example, in step S13, the tip R machining drill 53 is selected so that the value of R satisfying the above conditions (optimal R) is obtained, and the connecting wall surface 23 is formed at the optimum R. Further, in steps S11 and S12, the cutting depth of the pilot hole drill 51 and the drill 52 is adjusted so that the value of H satisfying the above conditions (optimal H) is obtained, and the length of the passage wall surface 21 in a predetermined direction is adjusted. Is formed to the optimum H. Similarly, the closed passage 21a and the small-diameter branch passage 32a are drilled so that the values of Da and D are the optimum Da and the optimum D that satisfy the above conditions.

The values of Da and D may be set based on the capacity required for the bag hole cylinder 10, and the drilling steps (drilling) in steps S10 and S20 may be executed so as to be the set values. .. In this case, after substituting those set values into the formula 1 and the formula 2, the two parameters R and H may be set so that all the conditions of the formula 1, the formula 2 and the formula 3 are satisfied.

As described above, in the manufacturing method of the present embodiment, the closed passage 21a is formed in the drilling step S10, the injection nozzle 60 is inserted into the closed passage 21a in the subsequent shot preparation step S31, and the injection nozzle 62 is inserted from the injection port 62 in the subsequent shot step S32. The shot material 90 is injected in the insertion direction. In the shot preparation step S31, the injection port 62 is positioned on the front side in the insertion direction of the small diameter branch passage 32a (branch passage). In the shot step S32, the shot material 90 injected from the injection port 62 is reflected by the tip wall surface 20a forming the tip portion of the closed passage 21a and collides with the intersecting portion 11.

According to this, when the shot material 90 collides with the intersecting portion 11 (corner portion), the shot material 90 is reflected and collided with the tip wall surface 20a of the body, so that the function of reflection by the conventional reflective material is applied to the bag hole cylinder. It will be given to 10 (body). Therefore, the conventional reflective material can be eliminated, and frequent replacement of worn parts can be suppressed.

Further, in the manufacturing method of the present embodiment, the connecting wall surface 23 has a shape curved to the side where the closed passage 21a is expanded. Therefore, when the connecting wall surface 23 has a non-curved shape, for example, a shot reflected by the tip wall surface 20a has a tapered shape in which the end portion of the ceiling wall surface 22 and the end portion of the passage wall surface 21 are connected by a straight line. The probability that the material 90 collides with the modified surface 11a can be improved.

Further, in the high-pressure fuel pump (fluid passage device) of the present embodiment, a closed passage 21a having a shape extending linearly in a predetermined direction and having a closed tip, and branch passages 31a and 32a branching from the closed passage 21a are provided. A metal body (bag hole cylinder 10) formed inside is provided. Of the wall surfaces forming the tip of the closed passage 21a, the surface perpendicular to the predetermined direction is the ceiling wall surface 22, the surface parallel to the predetermined direction is the passage wall surface 21, and the connecting wall surface connecting the ceiling wall surface 22 and the passage wall surface 21 is connected. Reference numeral 23 denotes a curved shape on the side that expands the closed passage 21a.

Therefore, it is possible to apply the residual compressive stress by colliding the shot material 90 with the intersecting portion 11 where damage due to stress concentration is a concern as follows. That is, when the injection nozzle 60 is inserted from the opening 21b of the closed passage 21a and the shot material 90 is injected from the injection nozzle 60 in the center line C1 direction (insertion direction) of the closed passage 21a, the shot material reflected by the connecting wall surface 23 is reflected. The 90 can be made to collide with the intersection with high probability. Therefore, since the body can be provided with the function of reflection by the conventional reflector, the conventional reflector can be eliminated and frequent replacement of worn parts can be suppressed.

Further, in the manufacturing method and the high-pressure fuel pump of the present embodiment, four parameters H, D, Da, and R are set so as to satisfy the conditions of the above-mentioned formulas 1 to 3. Da is the diameter of the closed passage 21a, D is the diameter of the small diameter branch passage 32a (branch passage), R is the radius of curvature of the connecting wall surface 23, and H is the center line C1 direction (predetermined direction) from the ceiling wall surface 22 to the small diameter branch passage 32a. ) Is the length. Then, these formulas 1 to 3 are obtained by numerical analysis so as to sufficiently increase the probability that the shot material 90 is reflected by the tip wall surface 20a and collides with the modified surface 11a.

Specifically, a range of combinations of parameters H, D, Da, and R having a high collision probability such that the maximum probability of collision with the modified surface 11a is 95% or more when the number of reflections is 2 or less is numerically analyzed. Equations 1 to 3 representing such a range have been calculated. Therefore, according to the present embodiment that satisfies the conditions of Equations 1 to 3, a high collision probability that is 95% or more of the maximum probability can be obtained, so that the work time required for shot peening can be shortened.

(Second Embodiment)
The bag hole cylinder 10 according to the first embodiment has one modified surface 11a that requires shot peening. On the other hand, in the present embodiment, as shown in FIG. 9, there are two modified surfaces 11a that require shot peening.

Specifically, the bag hole cylinder 10A according to the present embodiment includes two branch passages (small diameter branch passage 32a). The positions of the two small-diameter branch passages 32a in the injection nozzle insertion direction (vertical direction in FIG. 9) are the same. The two communication ports 32b are arranged so as to face each other. The other structures and manufacturing methods are basically the same as those in the first embodiment, but the shot material 90 injected from one injection nozzle 60 is shot peened at two modified surfaces 11a at the same time. different.

As described above, even in the present embodiment in which the modified surfaces 11a are present at a plurality of locations, in the shot preparation step S31, the injection port 62 is positioned on the front side in the insertion direction with respect to the small diameter branch passage 32a (branch passage). Then, in the shot step S32, the shot material 90 injected from the injection port 62 is reflected by the tip wall surface 20a forming the tip portion of the closed passage 21a and collides with the two intersecting portions 11.

Therefore, when the shot material 90 collides with the two intersecting portions 11 (corner portions), the shot material 90 is reflected and collided with the tip wall surface 20a of the body. Therefore, since the bag hole cylinder 10B (body) can be provided with the function of reflection by the conventional reflector to eliminate the need for the conventional reflector, frequent replacement of worn parts can be suppressed.

(Third Embodiment)
In the second embodiment, the positions of the two modified surfaces 11a in the injection nozzle insertion direction (vertical direction in FIG. 9) are the same. On the other hand, in the present embodiment, as shown in FIG. 10, the positions of the two modified surfaces 11a in the injection nozzle insertion direction are different.

Specifically, the bag hole cylinder 10C according to the present embodiment includes two branch passages (small diameter branch passage 32a). The positions of the two small-diameter branch passages 32a in the injection nozzle insertion direction (vertical direction in FIG. 10) are different. The diameter of the small-diameter branch passage 32a located on the back side (upper side in FIG. 10) in the insertion direction is smaller than the diameter of the small-diameter branch passage 32a located on the front side (lower side in FIG. 10). That is, the communication port 32b on the back side is smaller than the communication port 32b on the front side. The circumferential position of the small diameter branch passage 32a on the back side is the same as the circumferential position of the small diameter branch passage 32a on the front side. The diameter of the closed passage 21a in the portion communicating with the communication port 32b on the back side is smaller than the diameter of the closed passage 21a in the portion communicating with the communication port 32b on the front side.

The ceiling wall surface 22 according to the present embodiment is located in the closed passage 21a on the back side. Therefore, in the present embodiment, the passage wall surface 21 and the connecting wall surface 23 are located in the closed passage 21a on the back side, and the tip wall surface 20a including the passage wall surface 21 and the connecting wall surface 23 is located in the closed passage 21a on the back side. Of the wall surfaces forming the closed passage 21a on the front side, the surface parallel to the injection nozzle insertion direction (vertical direction in FIG. 10) is the front passage wall surface 21x, and the surface connecting the passage wall surface 21 and the front passage wall surface 21x is the front side. The side connecting wall surface is 23x. The front side connecting wall surface 23x has a shape curved to the side where the front side closed passage 21a is expanded.

Other structures and manufacturing methods are basically the same as those of the second embodiment, but the present embodiment is different in that the injection port 62 is located further in front of the small diameter branch passage 32a on the front side. ..

As described above, even in the present embodiment in which the modified surface 11a exists at different positions in the insertion direction, in the shot preparation step S31, the injection port 62 is positioned in front of the small diameter branch passage 32a (branch passage) in the insertion direction. .. More specifically, the injection port 62 is located closer to the front side in the insertion direction than the small diameter branch passage 32a on the front side. Then, in the shot step S32, the shot material 90 injected from the injection port 62 is reflected by the tip wall surface 20a forming the tip portion of the closed passage 21a on the back side and collides with the intersecting portion 11.

Therefore, when the shot material 90 collides with the two intersecting portions 11 (corners), the shot material 90 is reflected on the tip wall surface 20a of the body, the passage wall surface 21, the front side connecting wall surface 23x, and the front side passage wall surface 21x. To collide. Therefore, since the bag hole cylinder 10C (body) can be provided with the function of reflection by the conventional reflector to eliminate the need for the conventional reflector, frequent replacement of worn parts can be suppressed.

(Other embodiments)
Although the preferred embodiment of the invention has been described above, the invention can be implemented in various modifications as illustrated below without being limited to the above-described embodiment. Not only the combination of the parts that clearly indicate that the combination is possible in each embodiment, but also the partial combination of the embodiments even if the combination is not specified if there is no problem in the combination. Is also possible.

In the first embodiment, based on the simulation result shown in FIG. 8, formulas 1 to 3 are calculated so as to be in the range of parameters having a probability equal to or higher than a predetermined ratio of the maximum probability, and the predetermined ratio is set to 95%. It is set. On the other hand, the predetermined ratio may be set to a value larger than 95%, or may be set to a value less than 95% such as 90%, 85%, 80%.

In the first embodiment, when Da is in the range of 6.42 mm or more and 10 mm or less and D is in the range of 1 or more and 2.1 mm or less, the range of H is 0 mm or more and 3.2 mm or less. The range of R is preferably 0.5 mm or more and 3.2 mm or less. Further, the four parameters Da, D, R, and H may be set so that H> D after satisfying the equations 1 to 3, or H <D may be set.

In the first embodiment, the injection nozzle 60 is positioned so that Ha is in the range of 0 mm to 3 mm in step S31, and the shot material 90 is placed in step S32 so that the diffusion angle θ is in the range of 90 ° to 120 °. I'm spraying. On the other hand, the shot material 90 may be injected by setting Ha to 3 mm or more, or the shot material 90 may be injected by setting the diffusion angle θ outside the range of 90 ° to 120 °.

In each of the above embodiments, the connecting wall surface 23 is formed in a curved shape on the side where the closed passage 21a is expanded. On the other hand, the connecting wall surface 23 may have a tapered shape or a rectangular shape. In the second and third embodiments, the modified surface 11a that requires shot peening is at two locations, but it may be at three or more locations.

In the first embodiment, the injection nozzle 60 is positioned so that the center line C3 of the injection nozzle 60 and the center line C1 of the closed passage 21a coincide with each other. However, the center line C3 of the injection nozzle 60 is located on the closed passage 21a. Positioning may be performed so that the position deviates from the center line C1.

In the second embodiment, the two communication ports 32b are arranged at positions facing each other and are arranged at positions shifted by 180 ° in the circumferential direction, but they may be arranged at positions shifted from the facing positions.

In each of the above embodiments, in the drilling step S10, the closed passage 21a and the branch passage are drilled, but at least one of the closed passage 21a and the branch passage may be drilled with a laser.

In each of the above embodiments, the fluid passage device is applied to the high-pressure fuel pump, but any fluid passage device having a closed passage at the tip and a metal body having a branch passage branched from the closed passage is formed. , It can be applied to other than high pressure fuel pumps. For example, it may be applied to a fuel injection valve that injects fuel used for combustion in an internal combustion engine, or may be applied to a common rail that distributes and supplies high-pressure fuel to the fuel injection valve.

10, 10A, 10B ... Body, 11 ... Intersection, 20a ... Tip wall surface, 21 ... Passage wall surface, 21a ... Blocked passage, 22 ... Ceiling wall surface, 23 ... Connecting wall surface, 31a ... Large diameter branch passage (branch passage), 32a ... Small diameter branch passage (branch passage), 60 ... Injection nozzle, 62 ... Injection port, 90 ... Shot material, S10 ... Drilling process, S31 ... Shot preparation process, S32 ... Shot process.

Claims (4)

In a fluid passage device having a passage for circulating fluid,
A metal body (10,) in which a closed passage (21a) having a shape extending linearly in a predetermined direction and having a closed tip and a branch passage (31a, 32a) branching from the closed passage are formed inside. 10A, 10B)
Of the wall surfaces forming the tip portion on the closed side of the closed passage, the surface perpendicular to the predetermined direction is referred to as the ceiling wall surface (22), and the surface parallel to the predetermined direction is referred to as the passage wall surface (21). The surface connecting the wall surface and the passage wall surface is defined as a connecting wall surface (23).
The connecting walls, Ri shape der curved on the side to widen the closed channel,
Let D be the diameter of the branch passage.
The diameter of the closed passage is set to Da.
Let R be the radius of curvature of the connecting wall surface.
Let H be the length in the predetermined direction from the ceiling wall surface to the branch passage.
Let f1 (D, Da, R) be a function that specifies the lower limit of H with D, Da, and R as parameters.
Let f2 (D, Da, R) be a function that specifies the upper limit of H with D, Da, and R as parameters.
A fluid passage device that satisfies the conditions of the following formulas 1, 2 and 3 .
[Formula 1]
f1 (D, Da, R) = (0.019 x Da-0.0050 x D + 0.077) x R + (0.16 x Da-0.68 x D + 0.70)
[Formula 2]
f2 (D, Da, R) = (-0.018 x Da + 0.011 x D + 0.35) x R + (0.16 x Da-0.49 x D + 1.6)
[Formula 3]
f1 (D, Da, R) ≦ H ≦ f2 (D, Da, R) A metal body (10,) in which a closed passage (21a) having a shape extending linearly in a predetermined direction and having a closed tip and a branch passage (31a, 32a) branching from the closed passage are formed inside. 10A, 10B)
In the method for manufacturing a fluid passage device that allows fluid to flow through the closed passage and the branch passage.
A drilling step (S10) of forming the closed passage by drilling a portion of the body corresponding to the closed passage without penetrating the body.
After the drilling step, a shot preparation step (S31) of inserting the injection nozzle (60) having an injection port (62) for injecting the shot material (90) into the closed passage,
After the shot preparation step, a shot step (S32) of injecting the shot material from the injection port in the insertion direction and
Including
In the shot preparation step, the injection port is positioned on the front side in the insertion direction from the branch passage.
In the shot step, the shot material injected from the injection port is reflected by the tip wall surface (20a) forming the tip portion on the block side of the block passage, and the wall surface of the block passage and the wall surface of the branch passage. A method for manufacturing a fluid passage device that collides with an intersecting portion (11) at which the two intersects. Of the tip wall surfaces, the surface perpendicular to the predetermined direction is designated as the ceiling wall surface (22), the surface parallel to the predetermined direction is designated as the passage wall surface (21), and the surface connecting the ceiling wall surface and the passage wall surface is connected. The wall surface (23)
The method for manufacturing a fluid passage device according to claim 2 , wherein in the drilling step, the connecting wall surface is formed in a curved shape on the side where the closed passage is expanded. Let D be the diameter of the branch passage.
The diameter of the closed passage is set to Da.
Let R be the radius of curvature of the connecting wall surface.
Let H be the length in the predetermined direction from the ceiling wall surface to the branch passage.
Let f1 (D, Da, R) be a function that specifies the lower limit of H with D, Da, and R as parameters.
Let f2 (D, Da, R) be a function that specifies the upper limit of H with D, Da, and R as parameters.
The method for manufacturing a fluid passage device according to claim 3 , wherein in the drilling step, the closed passage and the branch passage are formed so as to satisfy the conditions of the following formulas 1, 2 and 3.
[Formula 1]
f1 (D, Da, R) = (0.019 x Da-0.0050 x D + 0.077) x R + (0.16 x Da-0.68 x D + 0.70)
[Formula 2]
f2 (D, Da, R) = (-0.018 x Da + 0.011 x D + 0.35) x R + (0.16 x Da-0.49 x D + 1.6)
[Formula 3]
f1 (D, Da, R) ≦ H ≦ f2 (D, Da, R)

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